/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.iotdb.metrics.metricsets.logback;

import ch.qos.logback.classic.Level;
import ch.qos.logback.classic.Logger;
import ch.qos.logback.classic.turbo.TurboFilter;
import ch.qos.logback.core.spi.FilterReply;
import org.apache.iotdb.metrics.AbstractMetricService;
import org.apache.iotdb.metrics.type.Counter;
import org.apache.iotdb.metrics.utils.MetricLevel;
import org.slf4j.Marker;

public class MetricsTurboFilter extends TurboFilter {
    private Counter errorCounter;
    private Counter warnCounter;
    private Counter infoCounter;
    private Counter debugCounter;
    private Counter traceCounter;

    MetricsTurboFilter(AbstractMetricService metricService) {
        errorCounter =
                metricService.getOrCreateCounter("logback_events", MetricLevel.IMPORTANT, "level", "error");

        warnCounter =
                metricService.getOrCreateCounter("logback_events", MetricLevel.IMPORTANT, "level", "warn");

        infoCounter =
                metricService.getOrCreateCounter("logback_events", MetricLevel.IMPORTANT, "level", "info");

        debugCounter =
                metricService.getOrCreateCounter("logback_events", MetricLevel.IMPORTANT, "level", "debug");

        traceCounter =
                metricService.getOrCreateCounter("logback_events", MetricLevel.IMPORTANT, "level", "trace");
    }

    @Override
    public FilterReply decide(
            Marker marker, Logger logger, Level level, String format, Object[] params, Throwable t) {
        // When filter is asked for decision for an isDebugEnabled call or similar test, there is no
        // message (ie format)
        // and no intention to log anything with this call. We will not increment counters and can
        // return immediately and
        // avoid the relatively expensive ThreadLocal access below. See also logbacks
        // Logger.callTurboFilters().
        if (format == null) {
            return FilterReply.NEUTRAL;
        }

        Boolean ignored = LogbackMetrics.ignoreMetrics.get();
        if (ignored != null && ignored) {
            return FilterReply.NEUTRAL;
        }

        // cannot use logger.isEnabledFor(level), as it would cause a StackOverflowError by calling this
        // filter again!
        if (level.isGreaterOrEqual(logger.getEffectiveLevel())) {
            switch (level.toInt()) {
                case Level.ERROR_INT:
                    errorCounter.inc();
                    break;
                case Level.WARN_INT:
                    warnCounter.inc();
                    break;
                case Level.INFO_INT:
                    infoCounter.inc();
                    break;
                case Level.DEBUG_INT:
                    debugCounter.inc();
                    break;
                case Level.TRACE_INT:
                    traceCounter.inc();
                    break;
            }
        }

        return FilterReply.NEUTRAL;
    }
}
